🔍 Key Concepts
• Trend analysis means repeated measurements over time to see changes or degradation patterns
• Some tools give you quantitative readings you can log (numbers over time); others give more of a one‑time condition picture
• On ships, think about what systems you routinely sample, record, and compare month to month or overhaul to overhaul
💭 Think About
• For each of I–IV, ask yourself: can I record values (temperature, ppm, microns, mm/s, kW, fuel rate, etc.) at regular intervals and plot them to see a trend?
• Which techniques are mainly used to detect developing faults over time, versus those used mainly as a snapshot diagnostic when a problem is suspected?
• Think about planned maintenance: which of these are commonly scheduled at intervals specifically to monitor long‑term changes in machinery condition?
✅ Before You Answer
• For each option, decide: does it naturally produce time‑series data (a set of readings over time) or mostly a single image/reading?
• Be clear on what lube oil analysis, vibration analysis, performance data analysis, and thermographic analysis are actually measuring on a ship’s machinery.
• Before choosing, eliminate any method that you would not normally trend on a graph across weeks/months in a condition‑monitoring program.